Can Too Much Caffeine Hurt You?

Clinical Herbalist Reviewed on January 5, 2019 by Paulina Nelega, RHPosted in Energy

Most people have a hard time getting up and moving in the morning without at least one cup of coffee. For others, their days don’t start until the second or third cup has been drunk.

Caffeine is seen as a “necessity” in today’s busy world, but very few people understand what caffeine really does to the body and what kind of side effects it can have. Even fewer people know how much caffeine is too much, or when it can start to hurt you. (If you’re on your fourth cup of joe while reading this, you might want to switch to water.)

Before you can understand how much caffeine it takes to cause harm, you must first understand how caffeine interacts with your body and mind.

What caffeine does to the body

Caffeine stimulates the nervous system and is actually a psychoactive drug, although it doesn’t usually affect us much because we take it in such limited amounts in our coffee, tea, soda and food.

When caffeine enters your body, it is absorbed into the blood stream and causes an increase in heart rate and blood flow. It blocks adenosine, a chemical that makes you tired, and increases adrenaline, a stimulating hormone. This results in improved mood, better functionality, higher alertness and less sleepiness in the mornings.

Caffeine remains in your body for around five hours, after which your body gets rid of it. It’s during this time that you may experience a “crash.”

Caffeine can also be addictive. Over time, your brain chemistry changes, including the addition of more adenosine receptors. If you suddenly stop ingesting caffeine after having it regularly, your brain may experience withdrawal symptoms because of the imbalance of receptors and stimulants.

How much caffeine is safe?

Typically, experts say that 300-400 milligrams (mg) of caffeine per day is safe for you.

However, you must remember that the amount that you get per serving will vary depending on what you’re ingesting. For most people, coffee is where they get their caffeine fix. But even then, the amount of caffeine in a Starbucks brew will be drastically different from a cup of instant coffee you make at home.

One 8oz cup of regularly brewed coffee at home usually provides around 135mg of caffeine. This means that two or three cups of coffee put you at the maximum amount of safe caffeine intake. A 1.5oz shot of espresso, though, contains around 77mg.

By contrast, an 8oz cup of black tea can provide between 40 and 70mg of caffeine, and a 12oz can of Mountain Dew soda has around 54mg.

To know how much caffeine your drink really has, look at the back of the drink or box, or check out an online index of caffeine content.

Going a little beyond that 400mg limit of caffeine probably won’t be too harmful to your health. Depending on your tolerance, you might experience the jitters or feel a little wired. However, experts say that when you begin taking 500-600 mg of caffeine a day, that’s when health problems can start.

Caffeine overdose

Having more than 400mg of caffeine a day is generally not recommended. Some people may have a higher tolerance for caffeine and can ingest more each day without feeling its effects, but the long-term effects of high doses of caffeine on the body are not good.

Too much caffeine can cause side effects such as tremors, insomnia and headaches. It is also known to worsen feelings of anxiety and restlessness. Gastrointestinal problems are also common.

It is also possible to “overdose” on caffeine if you have too much, but this limit is much higher. A caffeine overdose might cause even worse side effects, including an irregular heartbeat, dizziness, shortness of breath and even seizures.

It’s very important to pay attention to how your body is reacting to caffeine throughout the day and cut back if you experience side effects. If you think you’re experiencing a caffeine overdose, you’ll need to go to the doctor as soon as possible to have your heart rate monitored and receive treatment. This condition can be extremely serious and have lasting effects on your health.

Caffeinate responsibly

Caffeinated drinks like coffee and tea contain many healthy components like anti-inflammatories, antioxidants and more, so they aren’t inherently unhealthy to drink. However, because of their hidden caffeine levels, you need to be very careful when ingesting caffeinated food and beverages to make sure you’re not getting more than the recommended dose each day.

Remember, if you start to experience the shakes, dizziness, confusion or other side effects, the answer is not another cup of coffee! Drink some water, eat a snack and go to the doctor if necessary, and make sure to limit your caffeine intake in the future to stay healthy.

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Our Expert

Paulina Nelega, RH
Paulina Nelega, RH, has been in private practice as a Clinical Herbalist for over 15 years. She has developed and taught courses in herbal medicine, and her articles on health have appeared in numerous publications. She is very passionate about the healing power of nature.
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